It's nice to see these photos of Odense Zoo as it reminds me of my trip to Scandinavia last summer. Odense is an absolute gem of a zoo. I would rather visit Givskud or Odense any day of the week over the more famous (but outdated) Copenhagen Zoo.
@Fallax Odense is fantastic, but I'd go with Givskud as my favourite Danish zoo. Kristiansand (Norway) is a hugely popular, excellent zoo, plus there's some nice ones in Sweden. I have detailed reviews and photos of 24 Danish, Swedish and Norwegian zoos on this thread: